Glass ball

The choice of material depends entirely on the application. For industrial use, Borosilicate glass is preferred for its high thermal shock resistance and chemical stability. For decorative or optical purposes, K9 Crystal (Optical Glass) offers superior clarity and a high refractive index. If the application involves high-pressure environments, ensure the glass is tempered or heat-strengthened to prevent shattering.

For precision engineering (such as bearings or valves), you must specify the Grade (G10 to G1000). A lower grade number indicates higher precision. Ensure the sphericity (out-of-roundness) and diameter tolerance meet your technical drawings. Always request a Micrometer measurement report or a third-party inspection certificate to verify these dimensions before shipment.

If the glass balls are intended for toys or home decor, they must comply with EN71 (EU) or ASTM F963 (US) standards regarding physical safety and heavy metal content. For items in contact with food or beverages, FDA or LFGB certification is mandatory to ensure the glass does not leach harmful substances. Always verify the Lead (Pb) and Cadmium (Cd) levels through lab test reports.

Suppliers can provide various finishes including sandblasting (frosted effect), electroplating (metallic coating), internal laser engraving (3D patterns), and iridescent coatings (AB color). When sourcing, clarify if the coating is scratch-resistant and if it can withstand UV exposure without fading over time.

Glass is highly fragile; therefore, customized foam molding (EPE/EPS) or individual bubble wrap is essential. Insist that the supplier uses 5-layer corrugated export cartons and reinforces them with wooden pallets or crates for LCL (Less than Container Load) shipments. Including 'Fragile' and 'Handle with Care' labels in multiple languages is a basic but critical requirement.

Focus on Total Cost of Ownership (TCO) rather than just the unit price. Negotiate for lower sample fees that can be deducted from the bulk order. For long-term partnerships, ask for a tiered pricing structure where the price drops as your annual volume increases. Always confirm the mold fee if you require custom sizes, as this is a significant upfront cost.

Utilize the Secured Trading services provided by Made-in-China.com to protect your payment until delivery is confirmed. Never wire 100% of the payment upfront; a standard 30% deposit and 70% balance against the Bill of Lading (B/L) is common. Additionally, hire a third-party inspector (like SGS or Intertek) to perform a Pre-Shipment Inspection (PSI) to ensure the quality matches your requirements.

Check the HS Code (typically 7018 or 7020) to determine the import duties in your country. Be aware of anti-dumping duties that some regions (like the EU or USA) may impose on specific glass categories from certain manufacturing hubs. Ensure the supplier provides a Certificate of Origin (CO), which may help you qualify for preferential tariff rates under Free Trade Agreements.